Manhole cover locking mechanism



June 18, E946. A. J. lGILLET-rE 2,402,246

MANHOLE COVER LOCKING MECHANISM Filed March 6, 1944 Patented June 18, 1946 UNITED STATES PAITEPITL oFFlcE f MANHOLE .oovER' LOCKING MECHANISM Arthur .1. Ginette, Chicago, 11i. Application March 6, 1944, Serial No. 525,148` l 1 Claim.

My invention belongs to that general class of devices known as manhole covers, and more particularly to mechanism for removably locking the cover at the open end of the manhole.

`The invention has among its objects the prof duction of a device of the kind described which is simple, inexpensive, convenient, efficient and satisfactory. It has particlarly as an object the production of a manhole cover and locking means therefor whereby the manhole cover cannot be readily removedi by unauthorized persons.

Thev invention has as a further object the production of a locking mechanism of the kind described which cannot be manipulated or operated except by the use of a key of simple construction in the possession of one authorized to remove or replace the cover. A further object is the production of an auxiliary closure arranged to cover a keyhole through the manhole cover and which may be moved out of the way when it is desired to operate the locking mechanism at the under side of the manhole cover.

Many other objects an-d advantages of the construction herein shown and described will be obvious to those skilled in the art from the disclosure herein given.

To this end my invention consists in the novel construction, arrangement and combination of parts herein shown and described, and more particularly pointed out in the claim.

In the drawing, wherein like reference characters indicate like or corresponding parts:V

Fig. 1 is a plan View of my improved manhole cover in position at the mouth of a manhole;

Fig. 2 is a sectional view of the same taken substantially on line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken substantially on the line 3-3 of Fig. 2;

Fig. 4 is a sectional View taken substantially on line 4-4 of Fig. 2;

Fig. 5 is a plan view of an auxiliary closure arranged at the under side of the manhole cover;

Fig. 6 is a similar view of a modified construction; and

Fig. 7 is a view in elevation of a key suitable for unlocking the Icover as well as to move the auxiliary closure.

Referring to the drawing, I represents a manhole cover, generally of cast iron or other suitable material of the desired size and shape arranged to cover the mouth of a manhole 3 formed by the manhole structure 2. Ordinarily, a top annular member l of concrete or other suitable material is arranged at the mouth of the manhole, the same being provided with a ledge 5 upon -which the cover rests. 'when in Aclosed position. Y

Carried by the manhole cover at the underside is a locking bar 6 of a length to engage with the manholestructure, as shown, with the under face I of the top member 4. Carried at'the under side ofthe cover I is a threaded rod or bolt 8 provided with a head S, the bolt threadedly engaging at II) with the bar 6, the lower end of the-bolt being preferably headed or enlarged as indicated at Il. As shown,` the head `9 of the bolt is carried from a supporting member I2, I3 being a spacer are ranged between the member I2 and the cover, it being understood, however, that any equivalent for the member I2 and spacer I3 may be employed for the purpose. The member I2 also carries guides I4 which are arranged to guide the bar 6 when the bolt 8 is rotated and prevent rotation of the bar 6 relative the cover when the bolt is turned to lock or unlock the cover.

Provided in the cover is an opening or keyhole I6 which is in registry with the bolt head 9. The bolt as shown is provided with a recess Il for receiving the end I9 of a key I8, the end I9 being insertable through the opening I6 so that the bolt may .be engaged and turned from the exterior of the cover to raise or lower the bar 6. To prevent the admission of dirt into the recess I'I through the opening I5 in the cover I provide a closure or auxiliary cover 20 arranged at the under side of the cover I which may be secured in place by a member 2| rigidly secured to closure 20 and extending through the cover I, the same being provided with a recess 23 in which the end 24 of the key I8 may be inserted. The closure 20 is provided with an opening 22 which may be brought into registry with the opening I6 through the cover I so that the end I9 of the tool or key may be inserted through the opening I6 and engage the bolt 8 to turn it.

In the modied closure shown in Fig. 6, 25 represents the closure which may be secured in place on the cover by a small bolt or screw 26 having a recess 21 corresponding with the recess 23 in the bolt 2I. In this case the opening 28 in the closure and the bolt 26 are shown arranged off-center.

In applying the manhole cover to the manhole, the lbolt 8 is turned so that the locking bar 6 is spaced from the member I2 as shown in the dotted lines in Fig. 2. The cover I may then be tilted to permit one end o-f bar 6 to be seated and underlie the under face 'I of the ring 4 and then the opposite end of the bar 6 is seatedy below the ring 4, after which the cover I may be seated 3 on the face 5. Assuming the closure member 20 is as shown in Fig. 2 in the dotted position, the end I9 or key of the wrench I8 may be inserted through the opening I6 to engage the bolt head in the recess I1. As the bolt 8 is turned by means of the key or wrench, the bar 6 is moved up into engagement with the face 1, as shown in Fig. 2. The Wrench I 8 may then be removed and the end 24 inserted in therecess 23 of the bolt 2l and the bolt 2| turned,A thereby turning closure 20, to which the bolt 2| is rigidly secured, and rotating the same suiiiciently to close the keyhole or opening I6 at the under side of the closure. It will thus be obvious that the manholecover I is securely locked in place and the admission of dust, dirt, Water, etc. through the opening I6 tol the under side of the cover is prevented.v To remove the cover I the operations are reversed.

The device not only securely locks the` manhole cover in place, but prevents its unauthorized removal, thereby preventing the same from being stolen or being removed by children curious to see what the manhole is like. Where the same is in the street, the manhole cannot easily be displaced by vehicles lpassing over the same.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention; hence I do not wish to be understood as limiting myself to the exact form, construction, arrangement and combination of parts herein shown and described, or uses mentioned.

What I claim as new and desire to secure by Letters Patent is:

A locking mechanism for manhole covers and the like of the kind described for use on a manhole structure having an annular internal iiange at its upper end, and in combination, a circular cover, a supporting member, separate spacers located between the cover and supporting member and secured to the cover and supporting member, one at each side of the center of the cover to leave a free space between said spacers, a locking bar of greater length than the internal diameter `Vof said flange adapted to be engaged with the underside of the flange and at any place thereon, a bolt having a socketed head disposed in the space between said spacers and carried by said supporting member at the underside of the cover and threadedly engaging said locking bar, said cover' being provided with a key hole, opening through the same in registry with the bolt, and upright guide means carried by the supporting member for guiding the locking bar and preventing relative rotation between the cover and locking bar, said bolt being of a length to space the locking bar away from the cover sufficiently for one end of the bar, when the cover is tilted, to be inserted under the flange and the other end of the bar then passed through the opening, and the ends of the bar being drawn up against the iange by the bolt.

ARTHUR J. GILLETTE.` 

